1. The Field of the Invention
Devices, systems and methods developed in the context of this invention relate to solid-state refrigeration technology.
2. The Relevant Technology
Solid-state thermoelectric and thermionic devices capture great attention in the areas of thermal energy to electric power conversion and refrigeration. Captivating and useful properties of such devices include their reduced size, potential for further miniaturization, and their performance under operating conditions such that they are free of circulating fluids and moving parts.
The efficiency of such devices in their conventional forms is presently too low for their wide use in general household and industrial applications. Furthermore, the design of such devices typically depends strongly on material technology because of their characteristics. For example, thermoelectric and thermionic materials should have high electric conductivity and yet behave as very good thermal insulators. If the electrical conductivity were too low, resistance heating would detrimentally warm a thermoelectric or thermionic cooler, and if the material were not a good thermal insulator, the heat transported by the electric current would flow from the hot to the cold side. These functionalities in conventional devices are interwoven and appear inseparable. Accordingly, thermionic and thermoelectric materials are designed by choosing constituents such that the material has acceptable electrical conductivity and heat insulating properties. A disadvantage with this conventional approach is that it has the inherent limitations of the technology of the materials that are to be designed and of their constituents.
It is therefore desirable to provide thermionic and/or thermoelectric devices whose design is not limited by materials science and technology. It is also desirable to provide thermionic and/or thermoelectric devices whose efficiencies are improved with respect to those of conventional thermionic and/or thermoelectric devices.
The present invention provides solutions to problems encountered in the art. Solutions provided by the present invention include thermionic devices whose design is not limited by materials science and technology. In particular, device design according to the present invention is performed in terms of separate thermal insulation and electric conduction functionalities. Devices according to the present invention include multi-element solid-state devices with improved efficiencies.
These and other objects and features of the present invention will become more fully apparent from the following description and appended claims, or may be learned by the practice of the invention as set forth hereinafter.